ELFT HÍRADÓ

[tcsaba <tcsaba AT eik.bme.hu>]

                   M E G H Í V Ó - I N V I T A T I O N

    Seminar Series of the Department of Theoretical Physics at the
           Budapest University of Technology and Economics


                           Mihály Weiner
               (BUTE Department of Mathematical Analysis)


           How does a charged particle move in an external
                       electromagnetic field?


An electric charge moving in an external electromagnetic field can emit 
electromagnetic radiation. Thus, apart from the Lorenz force, one needs 
to consider the "recoil" caused by the emitted radiation. To put it in 
another way, the charge is affected by its own field. However, this is 
not so straightforward to take account of, as the field of a point 
charge at its location is singular.

The usual way to compute the motion of a charged particle in an external 
electromagentic field is to rely on the so-called Lorenz-Dirac equation. 
This equation has a number of known problems. In particular, it is a 
third order equation of motion, thus apart from initial position and 
velocity one needs to "prescribe" an initial acceleration to uniquely 
determine a solution. Also, it admits physically unacceptable runaway 
solutions.

Often these problems are treated in an ad-hoc manner. We take the 
viewpoint that the physically acceptable solutions of the Lorentz-Dirac 
equation are actually determined by some second order equation of 
motion. Then, postulating certain natural properties, in some cases we 
are actually able to determine a concrete form for this equation.

Időpont: 2016. szeptember 23. péntek, 10:15
Helyszín: BME Fizikai Intézet, Elméleti Fizika Tanszék,
Budafoki út 8. F-épület, III lépcsőház, szemináriumi szoba